1. Field of the Invention
This invention relates to a self-sticking cleansing block that is applied to a surface such that a rinse liquid disintegrates the cleansing block thereby cleaning, disinfecting and/or deodorizing the surface with active ingredients of the cleansing block. More particularly, this invention relates to a self-sticking disintegrating cleansing block for toilets or urinals.
2. Description of the Related Art
It is known that disintegrating blocks containing various components can be used for cleaning, disinfecting and/or deodorizing toilets or urinals. Such disintegrating blocks generally are immersed in the water tank (also known as the cistern) of a toilet or urinal, or are placed in a holder of some sort and then put “under-the-rim” (UTR) of the toilet bowl or urinal. Once put into place, either in the cistern or in the toilet bowl or urinal, the block slowly releases active ingredients and disintegrates into the water. In the case of a disintegrating block placed into the cistern, the block may fall to the bottom of the cistern, and then constantly be bathed with water. Such constant contact with the water requires a formulation of a certain type to ensure that the disintegrating block releases active ingredients and disintegrates at an appropriate rate. In the case of UTR products, such disintegrating blocks will disintegrate and release active ingredients each time that the toilet is flushed and the block is rinsed with the flush water. Numerous patents have issued relating to the various formulations for such disintegrating blocks.
For example, U.S. Pat. No. 4,477,363 teaches a solid cake comprising a free fatty alcohol; a buffered surfactant; a perfume; a salt; and a dye. The solid cakes are intended to be used in conjunction with a toilet tank dosing dispenser which automatically dispenses a ration of surfactant, perfume, and/or dye, and, optionally, other ingredients to the bowl of a toilet, responsive to the flushing of the toilet.
U.S. Pat. No. 4,820,449 teaches a cleaning block for the tank of flush toilets including sodium monoalkyl sulfate, a fatty acid alkanolamide, and a water-soluble inorganic alkali salt (e.g., sodium sulfate), and, optionally, calcium-complexing carboxylic acids or alkali salts thereof, perfume, dye, antimicrobial agents and other auxiliaries. The block is said to be distinguished by a particularly long useful life, by uniform dissolving behavior and by high cleaning power.
EP 0014979 describes a process for the production of flushing blocks for lavatory hygiene wherein a powder-form or granular mixture having anionic and/or nonionic surfactants; disinfectants or bleaches; an acid; alkaline or neutral salts, solid inorganic or organic acids and/or complexing agents; fillers; dyes and fragrances; binders; and inorganic salts capable of binding water of hydration is brought into contact with water and thereby solidified to form the block.
U.S. Pat. No. 5,863,876 describes a toilet cleansing block containing a polyacrylate polymer and a lauryl benzene sulfonate salt surfactant. The block is for immersion in toilet tanks, and inhibits toilet bowl ring and stain formation, particularly those caused by iron oxide.
U.S. Pat. Nos. 5,945,390 and 5,990,061 describe toilet cleansing blocks that contain an anionic surfactant such as a sulfonate, a linear primary alcohol, and a binder such as hydroxy ethyl cellulose. The block erodes very slowly, yet at essentially identical rates in hard or soft water. The block is for use with a dispenser for immersion in toilet tanks or under the rim of a toilet basin.
U.S. Pat. No. 6,184,192 discloses a toilet cleaning block including a chlorine releasing agent, a stabilizer, a dye, a binder, and an anionic surfactant wherein the chlorine releasing agent, stabilizer, dye, binder, and surfactant are blended together. The binder prolongs life and the stabilizer suppresses adverse interactions between the chlorine releasing agent and the binder, as well as between the chlorine releasing agent and the dye.
Many of the disintegrating blocks described in the patents noted above may be placed into the toilet tank (cistern), either by placing the block into a dispenser, or by simply placing the block in the tank. However, placement of the blocks in the cistern may not be convenient—particularly if the cistern is behind a wall as can occur with some toilet and urinal designs.
It would be much more convenient to be able to place a disintegrating block directly into the toilet bowl or urinal. However, conventional disintegrating blocks must be placed in a holder and then appended to the rim of the toilet bowl. See, for example, the dispensers of U.S. Pat. No. 4,777,670 and D464,107 which are suitable for holding a disintegrating block. The additional need for a holder makes the manufacturing of such an item more complex and more costly. The holder also makes this approach somewhat less environmentally friendly, due to the additional waste that is created.
Alternatives to disintegrating blocks have been proposed. U.S. Pat. No. 6,667,286 describes a viscous gel-like substance that may be applied directly to the inner surface of a toilet bowl for cleaning and/or disinfecting and/or fragrancing the toilet bowl. The substance can be applied from a suitable applicator directly onto the inner surface of the toilet bowl, to which the substance adheres. The substance remains on the inner surface of the toilet bowl even after being contacted with flush water, and typically the substance is only flushed away completely after a large number of flushes. The substance is also suitable for application to other surfaces such as urinals, lavatory or industrial sinks, showers, bathtubs, dishwashing machines and the like.
Various applicators for such adhesive gel-like substances have been proposed. For example, PCT International Patent Application WO 03/043906 discloses a syringe-type dispensing device suitable for use in applying such adhesive gel-like substances to a surface. PCT International Patent Application WO 2004/043825 also discloses a syringe-type dispensing device for applying such adhesive gel-like substances to a surface. While these applicators are believed to succeed in applying the adhesive gel-like substances to a surface, the additional need for an applicator makes the toilet cleaning product more costly.
Thus, there is a need for an under-the-rim disintegrating block that does not require the use of a holder or complex applicator such that the cost and waste associated with the disintegrating block is minimized.